But at home his position is less commanding as he faces open dissent in his party over the merits of holding an April 5 debate on secularism and Islam in this nation that strictly prohibits religious talk or religious symbols in state affairs.

But now the French president’s political allies, among others, are shaking their heads over the April 5 event. Prime Minister François Fillon says he will not participate. An open letter this week from 12 leaders of France's main religious groups called the event mistimed, confusing, and bound to “stigmatize the nation’s Muslim community.” They questioned the appropriateness of a political party using the state apparatus to hold a debate on religious identity.

Sarkozy insists on forging ahead, though his United Popular Movement (UMP) has not yet announced specifics for the debate.

Like his counterparts elsewhere in Europe, Sarkozy is picking up on mainstream concern about a growing Muslim presence. But he is more precisely concerned with the growing popularity of far-right leader Marine Le Pen, analysts say. Ms. Le Pen hit the airwaves in December with high-voltage criticism of Muslims who, when their mosques spill over on Fridays, “occupy public space" in praying on the street. She compared it to the Nazi occupation.

A likely challenger to Sarkozy in the 2012 presidential election, Le Pen recently rebranded Europe’s leading far-right party, the National Front, founded by her father, making it less hostile toward Jews and gays and more focused on Muslims and immigrants. Her National Front routed the UMP in local elections March 27.

Sarkozy faces internal dissent

That outcome, along with the failure of a Sarkozy-led national discussion in 2009 on “French identity,” widely seen as code for a discussion about Islam, has led many in Sarkozy’s party to say the debate idea either isn’t proper or isn't working politically.

This moment pits two wings of the Palace against each other. One side is championed by the party Secretary General Jean-François Copé, a rising figure who engineered France’s ban on publicly wearing the Muslim niqab, or full-face coverings. He argues for a fight on Le Pen’s far-right ground to show voters the president is listening.

Another wing, which includes the prime minister, says the French center-right must stick to its own mainstream values and not tread the extremes. “We should put an end to these debates,” said party stalwart François Barouin, who also happens to be the government spokesman.

On March 11, Sarkozy sacked the Palace “diversity adviser” for criticizing the debate, but the dissension has now gone past that kind of reprimand.

For now, Sarkozy is listening to Mr. Copé. As the debate over the debate began to melt the UMP’s reactor core, Copé published a letter “to a Muslim friend” (not an actual person), calling for Muslims to rally with Sarkozy's UMP against Le Pen's National Front.

“You are always the first one to tell me: the practice of Islam in a secular republic cannot condone the burqa, nor the prayers in the street, nor the rejection of gender equality," he wrote, continuing: "The National Front and the Islamists relish our divisions. They arouse them because they live off them. With this letter, I wish to tell you that we can stop them.”

Debating the debate

Meanwhile, the actual debate on secularism and Islam almost seems an afterthought. Essentially it hinges on the nation’s famed laïcité, or laws forbidding religious expression in public life, that date to a 1905 decree designed to limit the influence of the Roman Catholic Church but that applies to all faiths.

The UMP debate would examine whether the state should help fund mosques or play a role in the training and certification of imams, for example, on the argument that the religious demography of France, which today has some 6 million Muslims, is more diverse than a century ago.

Yet it is the debate about the debate that occupies the public bandwidth.

“The president is hunting on the extreme right margins,” says Pierre Haski, editor of Rue 89, an online daily and weekly magazine. “The debate over Islam is not interesting. It is a gimmick to show to National Front voters they can vote UMP.”